C# language theory question

Question

Given the following method,where I pass configuration byref, then loop through it using a foreach named collection. In the following code sample, will the values that I change in the loop be updated in the main object I passed through by ref, what I mean is NO shallow copies? Or can you spot any mistake I've made.

More specifically the line where I call config.Value = ..... the configuration object has a collection of configurations, so will these be updated in the main object (configuration) after this function is called?

Thanks in advance.

public static void DecryptProviderValues(ref MyConfiguration configuration)
    {
        foreach (var provider in configuration.Providers)
        {
            var configItems = provider.Configurations;
            foreach (Configuration config in configItems)
            {
                if(EncryptionManager.IsEncrypted(config.value))
                {
                    config.Value = EncryptionManager.Decrypt(config.Value);

                }
            }
        }
    }

Answer 1

Assuming that all the items here are classes (not structs), then yes, but actually there is no need for configuration to be passed as ref ; you are already passing a reference (by value), and you aren't re-assigning the reference, so no need for ref here at all . Your changes are preserved and available to the caller.

For exactly the same reason that this would work:

Configuration x = new Configuration();
Configuration y = x;
x.Value = "abc";
Console.WriteLine(y.Value); // writes "abc"

here, because Configuration is (presumably) a class , there is only one object, and two variables that refer to the same object (at a simplified level, they are glorified pointers to the same object).

Answer 2

There is no need to pass configuration by ref in your case, since in C# you're manipulating references to instances of classes already.

You would use ref to pass value types like int or struct by reference.